Magnetic resonance imaging of equine stifles: Technique and observations in 76 clinical cases

Abstract

Magnetic resonance imaging (MRI) of equine stifle disorders is challenging. We describe a routine technique for low-field stifle MRI under general anaesthesia in clinical cases and report the main findings. We hypothesised that MRI can be safely and routinely performed and portray bone and softtissue pathology. In this retrospective study, medical records of 76 stifles with positive response to intra-articular anaesthesia without abnormalities on conventional diagnostic imaging were reviewed for breed, age, gender, MRI anaesthesia time and findings. Under anaesthesia, limbs were extended in a rotating MR gantry. Different sequences in several planes were acquired in an average time of 62 min. In all horses, the stifle examinations were successful and complete. Typical MRI lesions included bone marrow lesions, osseous cyst-like lesions, cruciate desmopathy, meniscal tearing or a combination thereof. Retrospective reviewing confirmed that initial radiographic and ultrasonographic images failed to identify these lesions. Surgically accessible lesions were confirmed in arthroscopy if exploration was indicated. However, MRI was useful to estimate extent of cruciate and meniscal pathology as well as bone marrow lesions and bone cystic-like lesions more thoroughly. Our protocol allows for routine stifle MRI, independent of breed, age and gender. Based on our preliminary results, low-field stifle MRI is safe and can delineate bone and soft-tissue pathology. Low-field MRI appears to be a promising approach for better understanding stifle pathology and thus treatment and prognosis.

Ultrasonographic diagnosis of lateral meniscal rupture in two horses with severe lameness

“…2016; Waselau et al . 2020). While these modalities provide large amounts of information regarding osseous, cartilaginous and soft‐tissue structures, equipment availability and patient size generally preclude their widespread use, especially in large horses.…”

“…A recent study using low‐field MRI with an open gantry described stifle MRI findings in 76 horses ranging from ponies to Warmbloods (Waselau et al . 2020). Although not available at our hospital, it is unknown if this system could have accommodated the Percheron mare in our study.…”

An alternative arthroscopic approach to the caudal pouches of the equine lateral femorotibial joint

“…The finding of bilateral tearing of the popliteus muscle in this series were considered markedly outwit the range of normality which has been described for the popliteus tendon 5 , and suggests that a more considered evaluation of this structure is warranted. Also, a recent MRI study of 76 equine stifle cases 11 made no observation of popliteal injury, suggesting the condition is indeed rare or possibly the modality may not be ideally suited to assessing peripheral tendon lesions.…”

Diagnose und Therapie von Kniegelenkerkrankungen – ein Update

“…Aufgrund der limitierenden Anatomie sind nur ca. 30 % aller Strukturen arthroskopisch zugänglich, was häufig zu einer falsch negativen Befundung führen kann [7]. Die entsprechenden Zugänge sind detailliert beschrieben [14].Vorteile liegen in der Möglichkeit einer intraoperati-ven Sondierung und unmittelbaren Therapiemöglichkeit der erreichbaren Strukturen.…”

“…Martin Waselaustufen von Kreuzband-und Meniskusrissen erkannt werden. Allein mit der MRT können sehr schmerzhafte und lahmheitsauslösende Knochenödeme dargestellt werden[7]. Da keine ionisierende Strahlung generiert wird, sind keinerlei Anforderungen an den Strahlenschutz zu beachten.…”